Powder coating compositions are dry free flowing powders applied in the fusion coating process. A fusion coating process is a process in which a coating powder is distributed over a substrate and, when heated fuses to form a continuous film. The substrate may be heated or unheated when the powder is applied thereto. Heat supplied from the substrate or from an external source, such as an oven, causes the powder to fuse into the continuous film. Known fusion coatings processes for application of powder coating compositions to a substrate include electrostatic spraying, fluidized bed coating and hot flocking.
Powder coating compositions may be made of many different resin materials including polyurethanes, TGIC resins, Primid resin systems, epoxy resins, hybrid polyester and epoxy resin combinations (e.g., epoxy, epoxy-polyester), urethane-polyester, TGIC-free polyesters which are free of triglycidylisocyanurate (TGIC) and acrylic coating materials. Other components or constituents include curatives, flow aids, degassing agents, catalysts, pigments, modifiers, fillers and charge inhibitors.
Chemical agent resistance coatings (CARC) are coatings that resist the absorption of chemical warfare agents making decontamination easier to accomplish with vehicles, artillery pieces, missile launchers, aircraft, tanks and Humvee's. One of the problems facing CARC powder coating platforms for military applications is that current powder coating binder platforms formulated using epoxies, hybrids, certain polyurethanes, Primids, and TGIC's lack the required CARC properties for the gloss range less than 1.5@60 degree angle, required color tolerances, chemical resistance, and the absence of infrared detection, to provide exterior durability properties, which is outlined for Type III Coatings—Camouflage 383 Green, 686 Tan per Mil-PRF-32348. Previously there have not been any top coat CARC powder coatings available on the market which passed the specification requirements with the absence of a CARC primer system.